My oldest son was also born small due to placental issues. He did go through something similar, but it doesn't sound like it was anywhere that extreme. So, while I haven't had this type of major issue, I do know how I dealt with it when it did come up (which happened in stages). First, does she have a blanket or stuffed animal that she likes? I know many parents don't want their child to cary one around (I was one of them), but you should try it (if you haven't already). Get a blanket or stuffed animal, something that you know she would love, something soft and cuddly - wash it in what every you wash laundry with and then sleep with it. If you wear perfume constantly, you may spray a little on it as well. You want it to be your replacement. After you have done all this, introduce it to her. Make it out to be a big deal and how it smells like mommy and that it is there to protect her and keep her happy (just like mommy). Talk to her about when you aren't around how it will help her to think of you and know that you will come back soon.
Now, my son never really got attached to it, but he doesn't have an adictive personality. Just know that if you do introduce it now, in a few years it may be something that has to be dealt with taking it away. However, if you need that break (which I am SOOOO sure that you do) it just might work.
Good luck and let us know how it goes.
Sam